1. Technical Field
Exemplary embodiments of the present invention relate to a display substrate and to a method of manufacturing the display substrate. More particularly, exemplary embodiments of the present invention relate to a display substrate having a digital micro shutter (DMS) and to a method of manufacturing the display substrate.
2. Description of the Related Art
Generally, a display apparatus displays an image or data inputted by an input device. For example, a cathode ray tube, a liquid crystal display (LCD), a plasma display panel (PDP) and a field emission display have been used for the display apparatus.
Studies on applying a different mode for a display apparatus have been performed. For example, an organic light emitting display (OLED), a possible successor to the LCD and the PDP, is a next generation display apparatus, which has been commercialized. In addition, a display apparatus using a micro electro-mechanical system (MEMS), which has relatively high efficiency for light utilization and relatively fast switching, has been developed.
The display apparatus using the MEMS may include, for example, a first substrate on which a light blocking layer having at least one opening is formed, a digital micro shutter (DMS) having at least one opening, and a second substrate having a circuit which controls opening and closing of the DMS. The DMS moves horizontally by an electrostatic force when an electric signal is applied from the circuit.
For example, when the electric signal is applied to the DMS from the circuit, the DMS moves horizontally by the electrostatic force, so that the opening of the DMS is aligned with the opening of the light blocking layer and thus light passes through the openings. When the electric signal is not applied to the DMS, the DMS moves horizontally by an elastic force, such as, for example, a spring force, so that the opening of the DMS is not aligned with the opening of the light blocking layer and thus the light is blocked.
The DMS includes a metal layer to block the light during the closing of the DMS. If the thickness of the metal layer is increased, the transmitting light may be decreased. The thickness of the metal layer and reflectivity may be significant factors to determine a contrast ratio and a viewing angle in the display apparatus using the MEMS.
In depositing the metal layer on the DMS, the metal layer may be relatively thinly deposited at a side wall and at an edge portion of the DMS. Thus, the light may be leaked out during the closing of the DMS so that the contrast ratio may be decreased.